Radiation image storage panel and process for the preparation of the same

Abstract

In a radiation image storage panel comprising a support, a phosphor layer containing a stimulable phosphor and a binder, and a protective film superposed in this order, the improvement in which the thickness of the phosphor layer at the edge on at least two sides being opposite to each other is less than the mean thickness of the phosphor layer and the density of the stimulable phosphor at said edge is higher than the mean density of the stimulable phosphor in the phosphor layer.

We claim: 
     
       1. In a radiation image storage panel comprising a support, a phosphor layer containing a stimulable phosphor and a binder, and a protective film superposed in this order, the improvement in which the thickness of the phosphor layer at the edge on at least two sides being opposite to each other is thinner than the mean thickness of the phosphor layer and the density of the stimulable phosphor at said edge is higher than the mean density of the stimulable phosphor in the phosphor layer. 
     
     
       2. The radiation image storage panel as claimed in claim 1, wherein the thickness of the phosphor layer at the edge on all four sides is less than the mean thickness of the phosphor layer and the density of the stimulable phosphor at said edge is higher than the mean density of the stimulable phosphor in the phosphor layer. 
     
     
       3. The radiation image storage panel as claimed in claim 1, wherein the mean void ratio in the area from said edge of less thickness to the distance as long as one thirds of the mean thickness of the phosphor layer is 80% or lower based on the mean void ratio of the phosphor layer. 
     
     
       4. The radiation image storage panel as claimed in claim 1, wherein said edge of the phosphor layer having less thickness is coateed with a resin. 
     
     
       5. A process for preparing a radiation image storage panel comprising a support, a phosphor layer containing a stimulable phosphor and a binder, and a protective film superposed in this order by cutting a continuous radiation image storage panel sheet material, in which at least two edges of the panel being opposite to each other are formed by simultaneously cutting the continuous panel sheet material by means of a cutter having an angled edge. 
     
     
       6. The process for preparing a radiation image storage panel as claimed in claim 5, wherein all four edges of said panel is simultaneously formed by cutting the continuous sheet material at once by means of a cutter having an angled edge. 
     
     
       7. The process for preparing a radiation image storage panel as claimed in claim 5, wherein said cutter is angled on both sides at the edge. 
     
     
       8. The process for preparing a radiation image storage panel as claimed in claim 5, wherein a member for pushing the sheet material is provided adjacently to the cutter.